The signing is welcome news to 1 WTC’s owners, the Port Authority and the Durst Organization. Leasing at the tower — and for that matter at the whole WTC — has been quiet of late, even as major deals were being completed downtown at Brookfield Place, One New York Plaza and 55 Water St.

The Moody’s deal is the largest at 1 WTC, also home to Condé Nast, since High 5 Games took 87,600 square feet in November 2014.

Moody’s has 680,000 square feet in Larry Silverstein’s 7 WTC, but could not expand there because that tower is full.

The new lease brings 1 WTC to about 66 percent occupancy. Cushman & Wakefield’s John Cefaly and Gus Field represented Moody’s.